1. Field of the Invention
The invention relates to a technique of displaying condition information, and more particularly to a technique of displaying condition information at varying levels of granularity using a tree-like structure, which is usable to analyze a system or signal such as in a digital television environment.
2. Discussion of the Related Art
Television stations are integrating digital television (DTV) broadcasting equipment with their existing analog broadcasting equipment. Such DTV broadcasting equipment is very different than analog broadcasting equipment. The operators of the television stations need a way to verify that their digital broadcast signal, i.e., multiplex or data stream, is within standards described by the American Television Standards Commission (ATSC) or any other applicable standard. This is a non-trivial task because it is difficult to understand and interpret such data streams.
A data stream in a DTV broadcast environment is very complex and is generated by a battery of equipment such as encoders, PSIP generators, data servers, MPEG2 packet generators, multiplexers, etc. Much of this equipment is not only new to the broadcasters, but also new to the equipment vendors. As a result, broadcasts are often out of compliance with the relevant standards, so that many DTV receivers cannot receive them correctly.
Furthermore, it is not easy for broadcasters to determine whether or not their data stream is correct, even if they have an instrument that allows them to examine properties of the stream. Most users have great difficulty using existing stream monitoring and analysis tools because of their complexity and non-intuitive user interface.
An example of such an instrument is the stream analyzer manufactured and marketed by SENCORE. This instrument includes a few warning lights that are associated with very little explanatory information. A very practiced user of this instrument may debug error conditions in the data stream based upon his familiarity with the conditions that the warning lights might represent. But an average user generally has no idea how to get to the root of a problem reported by the warning lights.
To compound the difficulty of such analysis, it typically has to be performed under urgent circumstances, e.g., where the error is effectively disabling reception of the data stream by most of the would-be viewers. Therefore, there is a need for a technique of quickly detecting and analyzing the conditions of a system/product, which overcome these problems associated with the related art.